Burst resistant thin wall heat sink

ABSTRACT

An apparatus for cooling an electronic component has a planar top member of a thermal energy conductive material and a parallel planar bottom member of the material, the planar bottom member including a surface having regions configured for heat exchange contact with the electronic component. The planar top member has a plurality of stamped indent formations at a plurality of locations, each indent formation providing a contact surface such that the planar top member is affixed to the bottom member by braze or solder at each contact surface. Alternatively, the planar bottom member also has a plurality of stamped indent formations in alignment with indent formations of the top member. The planar top member is affixed to the bottom member by brazing or soldering each respective contact surface of an indent formation of the planar top member to an opposing contact surface of a corresponding indent formation of the parallel planar bottom member.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

This invention was made with Government support under Contract Numbers:B601996 and B604142 awarded by Department of Energy. The Government hascertain rights in this invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present disclosure is a conversion application of U.S. PatentApplication Ser. No. 62/143,587, the contents of which are whollyincorporated herein.

FIELD

The present disclosure generally relates to apparatus for coolingelectronic components and modules housed in electronic devices, such ascomputers, and more particularly to a burst resistant thin-walled coldplate or burst resistant thin-walled heat sink for cooling an electroniccomponent(s).

BACKGROUND

With the increase in heat dissipation from microelectronic devices andthe reduction in overall form factors, thermal management becomes a moreand more important element of electronic product design. Both theperformance reliability and life expectancy of electronic equipment areinversely related to the component temperature of the equipment.

Heat sinks function by efficiently dissipating thermal energy (i.e.,“heat”) generated from an object (e.g., electronic module ormicroelectronic component) into a cooler ambient, e.g., the air; and atleast transfer thermal energy from an object at a high temperature to asecond object at a lower temperature with a much greater heat capacity.

In a common design of a heat sink, a metal plate having a flat surface(e.g., a copper or aluminum base) is provided with an array of coolingstructures, e.g., combs or fin-like protrusions to increase the heatsink's surface area contacting the air and thus increase the heatdissipation rate. A high thermal conductivity of the metal base combinedwith its large surface area provided by the protrusions result in therapid transfer of thermal energy to the surrounding, cooler air.

Liquid cold plates, on the other hand, provide an alternative advantageover some air cooled solutions in high watt density applications and mayinclude tubed cold plates, flat tube cold plates, performance-fin coldplates and liquid-cooled chassis designs.

FIG. 1 shows a cross-sectional view of a current design of a portion ofa thin-plate-based cold plate or heat sink 10. In a current embodiment,the heat sink includes parallel formed planar members including a topthin-walled plate member 12, a bottom thin-walled plate member 15 andsidewall structures (not shown) that form a space or chamber 19 for airor fluid flow therein. Inserted within the chamber 19 affixed betweenparallel top thin-wall and bottom thin-wall plates are a plurality oftraverse oriented fins 25 that are oriented to provide one or morecommunicating air or liquid medium flow paths therein.

In order to withstand a “burst pressure” defined as the point at whichthe cold plate or heat sink will fail as a result of pressure (e.g., apoint determined by providing a liquid flow with force into thecommunicating flow path inside the hear sink and observing what portionswould be broken by the high pressures), the top thin-walled plate 12 andbottom thin-walled plate 15 are currently held together using separateplural support posts 20, two of which are shown in FIG. 1.

In such embodiments, each opposing end 30 of a respective post 20 issoldered or brazed onto the respective top and bottom thin plates asshown in FIG. 1. There is a great cost in implementing these posts, andtheir manufacture and widespread use in cold plate and heat sink devicesare becoming prohibitive.

BRIEF SUMMARY

There is provided a practical design for a heat sink or cooling platecooling device that implements stamped indent formations for affixing atop planar member to a bottom planar member of the cooling device.

In one aspect, the stamped indent formations are provided on a planartop member surface, each stamped indent formation providing a contactsurface that is soldered or brazed to the planar bottom member.

In one aspect, the stamped indent formations are provided on both aplanar top member surface, and on a planar bottom member surface, theplanar top member having a plurality of stamped indent formations at aplurality of locations, each indent formation providing a contactsurface when the planar top member is in a first orientation, and theplanar bottom member having a plurality of stamped indent formations ata plurality of locations in alignment with indent formations of the topmember, each indent formation providing a opposing contact surface whenthe parallel planar bottom member is in a second orientation. Eachcontact surface of indent formations of the planar top member is affixedto an opposing contact surface of a corresponding indent formation ofthe parallel planar bottom member by solder or braze.

Thus, in one aspect, there is provided a cooling apparatus for anelectronic device. The cooling apparatus comprises: a planar top memberof a thermal energy conductive material; a planar bottom member of thethermal energy conductive material, the planar bottom member including asurface having one or more regions configured for heat exchange contactwith the electronic device; a sidewall structure extending between thetop and bottom members and configured to enclose an area including theone or more regions, the planar top member, parallel bottom member andsidewall defining a chamber, and the planar top member having aplurality of stamped indent formations at a plurality of locations, atleast one the indent formation providing a contact surface, the planartop member and bottom member affixed using at least one the contactsurface.

In a further aspect, there is provided a cooling apparatus for anelectronic device or multi-chip module. The cooling apparatus comprises:a planar top member of a thermal energy conductive material; a planarbottom member of the thermal energy conductive material, the planarbottom member including a surface having one or more regions configuredfor heat exchange contact with the electronic device; a sidewallextending between the top and bottom members and configured to enclosean area including the one or more regions, the planar top member,parallel bottom member and sidewall defining a chamber, and the planartop member having a plurality of stamped indent formations at aplurality of locations, at least one the indent formation providing acontact surface when the planar top member is in a first orientation,the planar bottom member having a plurality of stamped indent formationsat a plurality of locations in alignment with indent formations of thetop member, at least one the indent formation providing a opposingcontact surface when the parallel planar bottom member is in a secondorientation, wherein the contact surface of indent formation of theplanar top member is affixed to an opposing the contact surface of acorresponding indent formation of the parallel planar bottom member.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a portion of a heat sink coolingdevice according to a conventional design;

FIG. 2 is a cross-sectional view of a portion of heat sink or cold platecooling apparatus according to a first embodiment of the presentdisclosure;

FIG. 3 shows conceptually a method step for joining the planar topthin-walled plate member and the parallel planar bottom thin-walledplate member of cooling apparatus according to the first embodiment;

FIG. 4 shows a cross-sectional view of a portion of a heat sink or coldplate apparatus according to a further embodiment of the presentdisclosure;

FIG. 5 shows conceptually a method step for joining the planar topthin-walled plate member and the parallel planar bottom thin-walledplate member of cooling apparatus according to the further embodiment;

FIG. 6 shows a perspective view of an exposed planar top plate 60 (orplanar bottom plate member) showing the plural formed stamped indentformations in areas of a planar surface surrounding cooling structures;

FIG. 6A shows a side cross-sectional view of a formed cooling apparatus70 having a planar first plate member with formed stamped indentformations joined to second planar plate member at the braze or solderlocations;

FIG. 6B depicts a zoomed-in portion 75 of the cross-sectional view ofthe formed cooling apparatus 70 of FIG. 6A;

FIG. 7 shows a perspective view of an exposed planar top plate member 60and a perspective view of an exposed planar bottom plate member 90showing the plural formed stamped indent formations in areas of a planarsurface surrounding cooling structures;

FIG. 7A shows a side cross-sectional view of a formed cooling apparatus100 having a planar first plate member with formed stamped indentformations joined to corresponding aligned stamped indent formations ofthe second planar plate by braze or solder; and

FIG. 7B depicts a zoomed-in portion 85 of the cross-sectional view ofthe formed cooling apparatus 100 of FIG. 7A.

DETAILED DESCRIPTION

This disclosure relates to a cooling apparatus, e.g., a heat sink orcold plate, having parallel thin plates, and a cost-effective method toimprove the capacity of parallel thin plates to withstand high burstpressure for the cold plate or heat sink applications. Instead ofsoldering separate posts to hold the top and bottom plates together, themethod includes stamping several (plural) indentations into the top thinplate surface, or both the top and bottom thin plate surfaces, in orderto make a similar post structure. Resulting indented formations have acontact surface that are each joined or affixed to the opposing platemember by soldering or brazing.

As mentioned herein, reference to a thin-walled plate refers to a plateor sheet of metal heat sink material, e.g., copper, aluminum, etc., of athickness ranging from 0.5 mm to 1.5 mm thick or any thickness that issuitable for effective cooling when secured in a heat exchange relationwith an underlying microelectronic component, e.g., an integratedcircuit chip, or electronic assembly, e.g., a multi-chip module (MCM).

FIG. 2 shows a cross-sectional view of a portion 50 of a heat sink orcold plate (“cooling apparatus”) according to one embodiment of thepresent disclosure. In the embodiment of the portion 50 depicted in FIG.2, the cooling apparatus includes parallel formed plate membersincluding a planar top thin-walled plate member 13, and a parallelplanar bottom thin-walled plate member 15. A sidewall portion (notshown) formed to extend between the planar top and bottom member about aperiphery thereof is provided to define a space or chamber 29 for amedia flow therein. The media may be air, or may be a liquid such aswater. In this embodiment of a cooling device, there are no separatepieces added in order to hold the top thin plate 13 and bottom thinplate 15 together in parallel. Rather, in the embodiment of the coolingdevice 10 shown in FIG. 2, the top thin plate 13 has plural stampedindentations formed such as the two stamped indentations 52A and 52Bshown in FIG. 2. In the orientation of planar top member 13 shown inFIG. 2, each stamped indentation 52A, 52B is a formation extending in adirection within said formed chamber that includes a respectiveunderside flat contact surface portion that is soldered or brazed asshown at 58 onto a top surface of the bottom parallel thin-wall baseplate 15, in order to prevent the chamber 29 from bulging underapplication of pressure. In the embodiment depicted in FIG. 2, thestamped indentations 52A, 52B are formed in the top thin-walled plate 14however, the bottom member in opposite orientation, may include theformed stamped indentations.

For its manufacture, a top thin-walled sheet of thermal energyconductive material, e.g., a metal, is located within a metal worksstamp press (not shown), i.e., a pressing machine or punching machine. Ametal stamping process in employed that uses a die to transform a flatthin metal plate (or sheet) into the plates as shown in FIG. 2 havingspaced apart indents. Any mechanical and hydraulic stamping press may beimplemented in which a metal stamping machine may cast, punch (in thedirection shown by arrows labeled “stamp”), cut and shape the top metalplate/sheet. The stamping of the top thin plate of the cooling device tocreate the three-dimensional shape shown in FIG. 2 includes inserting aflat sheet of metal into the die and then activating the mechanicalpress to create the indents in the planar thin-walled sheet. The metalstamping machine (not shown) may be programmed to provide a stamp havingthe desired shape and size for producing one or more indents.

In one embodiment, the stamp dies for a metal stamping press (not shown)may vary, and the resulting stamped indents 52A and 52B formed can be ofa depth of any shape. In one non-limiting embodiment, the length of astamp (and corresponding formed indent depth dimension) may rangeanywhere between 2 mm to 10 mm, however, other ranges are configurable.These may produce indents ranging between approximately 0.5 mm to 10 mmin depth.

In one embodiment, the stamp dies used in the pressing machine orpunching machine are of polygonal cross-section (not shown), e.g.,square or rectangular cross-sectional shape, such that the formed indentformations 52A, 52B are of a polygonal square or rectangular shape andof a length “L” substantially equal to a height of said chamber 29. Inone embodiment, the stamp dies used in the pressing machine or punchingmachine are circular cross-sectional shape such that the formed indentformations 52A, 52B are of a cylindrical shaped of a length “L”substantially equal to a height of said chamber 29. In one embodiment,the height of the chamber ranges from between 0.5 mm to 10 mm, or frombetween 1 mm to 8 mm in depth. It is understood that indent depths areconfigurable beyond the ranges as specified. A diameter or width of theformed indent formation shape ranges anywhere from between 1 mm to 10mm.

As further shown in FIG. 2, the cooling apparatus portion 50 furtherincludes a cooling structure 28 comprising an array of cooling fins,pins, or like structures 26 that extend from the bottom thin base plate15 to a planar surface portion 53 of the top thin-walled plate 13defining a top wall for the chamber 29. The underlying contact surfaceformed at each indented formation 52A, 52B of the top-thin walled platethat is brazed or soldered onto the bottom thin base plate 15 to holdthe plates 13, 15 together, obviates the need for separate posts whilemaintaining strength to withstand application of a pressure according tothe needs of the cooling application. For example, depending upon theapplication, the devices may be able to withstand burst pressures of 150psi. and beyond.

FIG. 6 shows a perspective view of an exposed planar plate member 60oriented as a planar bottom plate member according to one embodimentshowing the plural formed stamped indent formations 52 in areas of aplanar surface not including the cooling structures 28. A sidewall 65 isshown formed about the peripheral edge of the planar bottom plate member60 and is of a height substantially commensurate with the height of atop surface of the cooling structures 28. Inlet and outlet orificeconnection 68A, 68B are provided and formed to extend external to asurface of the cooling member for connection to a media source, e.g.,liquid water.

FIG. 6A shows a side cross-sectional view of a formed cooling apparatus70 having a planar first plate member 60 with formed stamped indentformations 52 joined to a second planar plate member 15 at the braze orsolder locations and defining chamber regions 29 for placement of thecooling structures (not shown). FIG. 6B depicts a zoomed-in portion 75of the cross-sectional view of the formed cooling apparatus 70 of FIG.6A. In the portion 75 depicted, each stamped indent formations 52 ofplanar first plate member 60 is shown with each contact surface 58 of anindent soldered or brazed to the inside surface 17 of the planar secondplate member 15.

FIG. 3 shows conceptually a method step for joining the planar topthin-walled plate member 13 and the planar bottom thin-walled platemember 15. In this embodiment, the top thin-walled plate 13 has beenprior stamped to include indented portions 52A, 52B which, in theembodiment shown, each provide a respective flattened underside bottomsurface portion 58A, 58B used to join a bottom plate. Further, in thisembodiment, an array of cooling structures, e.g., fins 26 are shownprior to positioning on a surface of the planar bottom member 15 of theplate 13. In a non-limiting embodiment, the length of each of the fins26 is commensurate with the depth of the formed indents 52A, 52B. In anon-limiting embodiment, both an inner surface 14 of the planar bottomplate member 15 and an opposing inner surface of the planar top platemember 13 may have a solder or braze paste material coated thereon tofacilitate a subsequent soldering or brazing step. In one embodiment,the planar bottom member 15 having cooling structure 28 located thereonat pre-determined regions may be fixed in orientation, and the top thinplate 13 having the stamped indentations 52A and 52B registered in thedirection indicated by solid arrows relative to the fixed bottomparallel thin-wall base plate 15 to join onto the bottom base plate 15and this structure is subsequently placed in an oven and subject tosoldering or brazing temperatures sufficient to affix the top and bottomplate members together. In this embodiment, each respective flatunderside bottom surface portion 58A, 58B of respective indents 52A, 52Bof top parallel plate 13 is soldered or brazed to a top surface 14 ofthe bottom thin-wall base plate 15. In an alternate embodiment, the topparallel plate 13 may be fixed in orientation and the bottom plate 15having cooling structure 28 located thereon at pre-determined regionsmay be registered relative to the top plate 13 in the directionindicated by broken arrows to join onto the top plate member 13 and thisstructure is subsequently placed in an oven and subject to soldering orbrazing temperatures sufficient to affix the top and bottom platemembers together.

FIG. 4 shows a cross-sectional view of a portion of a heat sink or coldplate cooling apparatus device 80 according to a further embodiment ofthe present disclosure. As in the first embodiment, the coolingapparatus includes parallel formed plate members including a planar topthin-walled plate member 13, and a parallel planar bottom thin-walledplate member 16. A sidewall portion (not shown) formed to extend betweenthe planar top and bottom member about a periphery thereof is providedto define a space or chamber 39 for a media flow therein. The media maybe air, or may be a liquid such as water. In this embodiment of acooling device, there are no separate pieces added in order to hold thetop thin plate 13 and bottom thin plate 16 together in parallel. Rather,in the embodiment of the cooling device 80 shown in FIG. 4, both the topthin-walled plate 13 and a bottom thin-walled plate 16 are each providedwith a respective plurality of stamped indented formations in alignment,wherein the indented formations are oriented in opposed directions andare soldered or brazed together. That is, in the embodiment depicted inFIG. 4, not only does the top thin-walled parallel plate 13 includerespective indent formations 52A, 52B, each having underside surfacecontact surface as in the embodiment of FIG. 2, but the bottomthin-walled parallel plate 16 also include the same plurality of indents72A, 72B, each respective indent formed to include a respectiveflattened, contact surface. When in an opposed orientation relative tothe orientation of the top plate 13, the respective flattened, contactsurfaces of indents 72A, 72B are joined by braze or solder to respectivealigned surface contact portions of respective indents 52A, 52B in orderto affix the top thin-walled plate 13 and the bottom thin-walled plate14 together with force sufficient to prevent the cooling chamber 39therein from bulging under application of pressure. For example, eachtop thin-walled plate 14 and bottom thin-wall plate 16 is first stampedwith a stamp press in order to form the respective indents (as shown bythe sets of arrows labeled “stamp” representing the stamp direction usedin providing the respective indent). It is understood that a singleprocess may be used to form the indented top plate 14 and indentedbottom plate 16 (as the top and bottom plates are interchangeable whenoppositely oriented). The cooling device portion 80 of this furtherembodiment further includes an array 28 of cooling fins 27 that areaffixed in the chamber and extend between the bottom thin base plate 16to the top thin plate portion surface within the chamber 39 forinfluencing air or liquid flow. The indented portions 52A, 52B of thetop thin-walled plate 13 being brazed or soldered to the respectiveindented portions of the bottom thin-walled base plate 16 obviates theneed for separate posts while maintaining strength to withstand burstpressure.

As in the first embodiment, the stamp dies used in the pressing machineor punching machine are of a polygonal, e.g., square or rectangularcross-sectional shape, or are circular or cylindrical. In thisembodiment, as depicted in FIG. 4, the formed stamped indent formations52A, 52B in the planar top plate member 13 and the formed stamped indentformations 72A, 72B in the planar bottom plate member 16 are of a length“L/2” such that when underside contact surface of each correspondingstamped indent formations 52A, 52B are soldered or brazed to stampedindent formations 72A, 72B, the total height of said chamber 39 is thesame length L as in the first embodiment.

As further shown in FIG. 4, the cooling apparatus portion 80 furtherincludes the cooling structure 28 comprising an array of cooling fins,pins, or like structures 27 that extend from a planar surface portion 73of the planar bottom thin plate 16 to a planar surface portion 53 of thetop thin-walled plate 13 defining a top of the chamber 39. Theunderlying contact surface formed at each indented formation 52A, 52B ofthe top-thin walled plate that is brazed or soldered onto the bottomthin base plate 15 to hold the plates 13, 15 together obviates the needfor separate posts while maintaining strength to withstand applicationof a pressure.

FIG. 7 shows a perspective view of an exposed planar plate member 60, asdescribed with respect to the embodiment of FIG. 6, which may be aplanar top plate member, and a corresponding exposed perspective view ofan underside of planar bottom plate member 90. In this embodiment, thecorresponding planar bottom plate member 90 is shown having the pluralformed stamped indent formations 72 therein in areas of the planarsurface that directly correspond to the plural formed stamped indentformations 52 formed in the parallel planar top member 60. The planarbottom plate member 90 is shown having regions 48 corresponding tolocations that are secured to the electronic device, e.g., chip or MCM,and where cooling structures 28 are to be affixed inside the chamber.Further shown in FIG. 7 are respective inlet and outlet orificeconnections 98A, 98B are provided and formed to extend external to asurface of the cooling member for connection to a media source, e.g.,liquid water.

FIG. 7A shows a side cross-sectional view of a formed cooling apparatus100 having a planar first plate member 60 with formed stamped indentformations 52 joined to contact surfaces of formed stamped indentformations 72 of second planar plate member 90 at the braze or solderlocations and defining chamber regions 39 for placement of the coolingstructures (not shown). FIG. 7B depicts a zoomed-in portion 85 of thecross-sectional view of the formed cooling apparatus 70 of FIG. 6A. Inthe portion 85 depicted, each stamped indent formation 52 of planarfirst plate member 60 is shown with each contact surface of an indentsoldered or brazed (affixed) to an opposing contact surface of acorresponding stamped indent formation 72 of planar second plate member90.

FIG. 5 shows a method step for joining the planar top thin-walled platemember 13 and the planar bottom thin-walled plate member 16 of theembodiment of FIG. 4. In this embodiment, the planar top thin-walledplate 13 has been prior stamped to include indented portions 52A, 52Bwhich, in the embodiment shown, each provide a respective flattenedunderside bottom surface contact portion 58A, 58B, and the planar bottomthin-walled plate 16 has been prior stamped to include indented portions72A, 72B which, in the embodiment shown, each provide a respectiveflattened underside bottom surface portion 78A, 78B. With the planarbottom thin-walled plate member 16 in opposed orientation relative tothe top thin-walled plate member 13, and with all interior surfaces 53,73 coated with a braze or solder paste material to facilitate asubsequent soldering or brazing step, in one embodiment, the planarbottom member 16 having cooling structure 28 located thereon atpre-determined regions may be fixed in orientation, and the contactsurfaces 58A, 58B of the stamped indentations 52A and 52B of top thinplate 13 registered in the direction indicated by solid arrows relativeto the fixed bottom parallel thin-wall base plate 15 to join therespective contact surfaces 78A, 78B of the stamped indentations 72A and72B of top thin plate 16, and once joined, this structure issubsequently placed in an oven and subject to soldering or brazingtemperatures sufficient to affix the top and bottom plate memberstogether. In an alternate embodiment, the top parallel plate 13 may befixed in orientation and the bottom plate 16 having cooling structure 28located thereon at pre-determined regions may be registered relative tothe top plate 13 in the direction indicated by broken arrows to joinonto the top plate member 13 and this structure is subsequently placedin an oven and subject to soldering or brazing temperatures sufficientto affix the top and bottom plate members together at contact surfaceinterfaces.

Thus, whether formed for application as a cold plate or heat sink, thestructure and methods described herewith improve the capacity ofparallel thin plates to withstand a high burst pressure.

The teachings herein may be implemented to enhance reliability of heatsink devices such as the heat sink device described in commonly-ownedU.S. Pat. No. 8,736,048. The whole contents and disclosure of U.S. Pat.No. 8,736,048 are incorporated herein by reference as if fully set forthherein. This U.S. Pat. No. 8,736,048 in particular, is directed to heatsink devices having lateral compliance feature.

While the disclosure has been described in terms of specificembodiments, it is evident in view of the foregoing description thatnumerous alternatives, modifications and variations will be apparent tothose skilled in the art. Various embodiments of the present disclosurecan be employed either alone or in combination with any otherembodiment, unless expressly stated otherwise or otherwise clearlyincompatible among one another. Accordingly, the disclosure is intendedto encompass all such alternatives, modifications and variations whichfall within the scope and spirit of the disclosure and the followingclaims.

What is claimed is:
 1. A cooling apparatus for an electronic devicecomprising: a planar top member of a thermal energy conductive material;a planar bottom member of the thermal energy conductive material, theplanar bottom member including a surface having one or more regionsconfigured for heat exchange contact with the electronic device; asidewall structure extending between said planar top member and saidplanar bottom member and configured to enclose an area including saidone or more regions, said planar top member, said planar bottom memberand said sidewall structure defining a chamber and the planar top memberhaving a plurality of first stamped indent formations at a plurality oflocations, at least one of said first stamped indent formationsproviding a contact surface positioned on an inner surface of the planartop member, an outer surface of the planar top member being indentedtoward the planar bottom member, the planar bottom member having anopposing contact surface positioned on an inner surface of the planarbottom member, an outer surface of the planar bottom member being flatwithout stamped indent formation, wherein said contact surface of the atleast one of the first stamped indent formations is affixed to theopposing contact surface of the planar bottom member, and the planarbottom member having no stamped indent formation, an inlet orificepositioned at a first end of the planar bottom member and an outletorifice positioned at an opposing end of the planar bottom member andwhich extend beyond an external surface of the planar top member forconnection to a liquid media source, and one or more cooling structureformations affixed within said chamber at locations in alignment saidone or more regions, said one or more cooling structure formationscomprising an array of fins or blades extending between the planarbottom member to the planar top member within the chamber and orientedfor directing a flow of a liquid media within said chamber.
 2. Thecooling apparatus as claimed in claim 1, wherein the planar top memberand the planar bottom member are affixed at a location between theplanar top member and the planar bottom member by one of solder or brazematerial.
 3. The cooling apparatus as claimed in claim 1, wherein atleast one of the first stamped indent formations is of a polygonalsquare or rectangular shape of a length equal to a height of saidchamber.
 4. The cooling apparatus as claimed in claim 1, wherein atleast one of the first stamped indent formations is of a circular orcylindrical shape of a length equal to a height of said chamber.
 5. Thecooling apparatus as claimed in claim 4, wherein the height of saidchamber ranges from between 0.5 mm to 10 mm.
 6. The cooling apparatus asclaimed in claim 5, wherein a diameter of said cylindrical shape rangesanywhere from between 1 mm to 5 mm.
 7. The cooling apparatus as claimedin claim 5, wherein said sidewall structure is formed about a peripheryof one of said planar top member or said planar bottom member.
 8. Thecooling apparatus as claimed in claim 1, wherein the plurality ofcooling structure formations are spaced apart between the inlet andoutlet orifices, more than one of the first stamped indention formationsare disposed between adjacent cooling structure formations of theplurality of cooling structure formations.
 9. The cooling apparatus asclaimed in claim 8, wherein one of the cooling structure formations ispositioned next to the inlet orifice, and another of the coolingstructure formations is positioned next to the outlet orifice.